1. Field of Invention
The present invention relates to a stethoscope which can be used by skilled medical personnel in conjunction with the standard blood pressure sphygmomanometer which would simultaneously measure the pulse rate as the blood pressure is being measured.
2. Description of Prior Art
Nurses, emergency medical technicians, medical assistants, physicians, and other medical personnel frequently require the recording of the vital signs. Every patient encountered in medical offices and outpatient clinics generally require the taking and recording of the vital signs. The major components of said signs include the blood pressure and the pulse rate. Thus, the measurement of the vital signs is an integral part of any medical encounter.
The blood pressure most commonly is obtained with the use of a stethoscope and a sphygmomanometer. The sphygmomanometer consists of an elongated air bladder termed the cuff which is wrapped around an arm of a human patient and air is pumped into said cuff thereby increasing the pressure to a point that the arterial pressure is surpassed and the artery is occluded. The air pressure is then gradually decreased to some level at which Korotkoff sounds (i.e. sounds created by the vibrating collapsed vessel walls as blood is allowed through) can be heard by the use of the diaphragm of a standard stethoscope held directly over the artery. The systolic and diastolic blood pressures are so obtained by auscultating the first and last audible Korotkoff sounds, respectively.
A pulse rate is normally obtained by palpating a peripheral arterial pulse and counting them. This is routinely done by locating and then palpating the radial artery at the wrist, finding a suitable time piece, then counting the number of beats felt over a timed period, usually 10 to 60 seconds, and multiplying that number by the appropriate number to determine the number of pulses per minute. This number is then termed the pulse rate or pulse.
This method is not only time consuming, but may be open to large inherent error. The observer must not be distracted from his count lest he forget the number of beats or the reference mark of the time piece utilized. Medical personnel are often in a hurry and in a setting in which one could be easily distracted. The action of locating the radial artery and waiting for the time piece to come to an appropriate numeral is time wasting.
Heretofore, devices have not utilized the readily available standard blood pressure sphygmomanometer and a stethoscope to also measure the pulse rate simultaneous to the blood pressure measurement. The stethoscope in U.S. Pat. No. 4,436,096 to Dyck, 1984 Mar. 13, responded to heart sounds and since there are two heart sounds per heart beat, the signals were processed in an elaborate manner necessitating a much larger and heavier device and not meant to be used in conjunction with a sphygmomanometer. The apparatus in U.S. Pat. No. 4,624,262 to Berger, does not utilize the Korotkoff sounds and instead uses a dynamometer to respond to arterial pulsations. The apparatus of U.S. Pat. No. 3,978,848 to Yen, et. al., is a more complicated device and is not incorporated into a stethoscope.
Medical personnel are inherently distrustful of any device which does not allow them continued hands on care and which does not rely upon human quality control. Patients also require and demand a certain amount of attention with hands on medical care which multiple electronic devices and high technology have gradually eroded.
Therefore, the need exists for a portable light weight stethoscope which could be used in conjunction with the standard blood pressure cuff to obtain a pulse rate while measuring the blood pressure in a routine fashion.